Midspan patch panel with compensation circuit for data terminal equipment, power insertion and data collection

ABSTRACT

A compensating advanced feature patch panel that can include removable modular or fixed electronic components located directly on the patch panel which are separately or in combination capable of providing advanced features such as device detection and power insertion. The patch panel provides communications between an insulation displacement connector (IDC) at a PD/User end, and any standard interface type using unshielded twisted pair cables, such as an RJ45 connector at a switch end at performance levels of at least category 3, 5, 5e, 6 and/or higher (e.g. 6e or 7) and equivalent performance levels as required by compensating for the active electronics used in providing advanced features through the use of inductive, capacitive and reactive circuit elements to compensate for advanced feature electronics.

REFERENCE TO RELATED APPLICATIONS

Related subject matter is disclosed in a U.S. patent application ofAbuGhazaleh et al., entitled “Midspan Patch Panel With CircuitSeparation For Data Terminal Equipment, Power Insertion And DataCollection”, Ser. No. 10/791,292 filed concurrently herewith and thesubject matter of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to a patch panel replacement deviceincluding advanced features for providing power and data collection inassociation with attached network devices while providing at leastcategory 3, 5, 5e, 6 and/or higher (e.g. 6e or 7) and equivalentperformance levels as required. More particularly, the present inventionrelates to a patch panel printed circuit board including modular orfixed electrical components for use with providing advanced features andfurther including compensation circuit elements to minimize the adverseeffects of electronics required for providing such advanced features.

BACKGROUND OF THE INVENTION

The convergence of telecom and datacom technologies, as well as theblurring distinction between the system side and the cabling system ofnetworks is driving a continuous evolution of structured cabling. Userexpectations and dependence on local area network (LAN) performance iscreating an expectation beyond operational speed and reliability tofurther include device tracking and system management. Currently,limited progress has been made in such areas due to the impact ofproposed improvements upon operational speed. As hubs and switches dealin logical addresses and network maps, asset location and connectionmanagement is best addressed through the cabling system. Development ofadvancements must address several evolving system features andrequirements such as the detection of connected devices, including theaddition, removal and/or movement of such devices accessing the systemand the provision of power to connected devices.

The movement of devices accessing the system is one of severalconsiderations during improvement developments. As described in U.S.Pat. No. 6,350,148, issued Feb. 26, 2002, to Batolutti et al., thesubject matter of which is incorporated herein by reference, manybusinesses have dedicated telecommunication systems that enablecomputers, telephones, facsimile machines and the like to communicatewith each other through a private network, and communicate with remotelocations via a telecommunications service provider. In most buildings,the dedicated telecommunications system is hard wired usingtelecommunication cables that are coupled to individual service portsthroughout the building. The wires from the dedicated service portstypically extend throughout the building and terminate at a patchingsystem that is used to interconnect the various telecommunication lines.The patching system is usually located within a telecommunicationscloset and is most often positioned on a mounting frame that includes anumber of racks or patch panels to which each telecommunication line isterminated. The patch panels include a number of port assemblies, suchas RJ-45 telecommunication connector ports, and each telecommunicationline is terminated to the patch panel in an organized manner.

One example of device movement considerations as disclosed in theBatolutti patent includes assigning one or more employees their owncomputer network access number exchange so that the employee caninterface with a company main frame computer or computer network. Asemployees or equipment are moved, patch cords in a typicaltelecommunications closet are rearranged and new positions are manuallydocumented using either paper or computer based logs. However,technicians often neglect to update the arrangement log each time achange is made. To correct this, manual tracing of the patch cord mustbe performed which can be both time consuming and prone to furthererrors.

Detecting connected devices is another consideration during improvementdevelopment which is commonly required for security purposes in manyapplications. Details of several examples of such detection issues aredisclosed in U.S. Pat. No. 5,406,260, issued Apr. 11, 1995, to Cummingset al., the subject matter of which is incorporated herein by reference.A number of device detection methods have been developed for guardingagainst the unauthorized removal of electronic equipment, includingmethods that require the actual physical attachment of a security cordto each piece of protected equipment or the attachment of non-removaltags to the equipment. However, these methods require rather expensivesensing devices and are not very practical in all cases. In the devicedetection method disclosed in the Cummings patent, an isolation powersupply is used to provide a low current DC power signal to eachcommunication link and thereafter, monitor a circuit loop createdthrough a DC resistive termination between the communication link and aremote device. Any interruption between the communication link and theremote device, such as the removal of the device from the communicationlink, disrupts the circuit loop and triggers an alarm.

Additional methods of circuit loop device detection also include thesensing of a current loop that is physically coupled to the protectedequipment. One such method is disclosed in U.S. Pat. No. 4,654,640,issued Mar. 31, 1987, to Carll et al., the subject matter of which isincorporated herein by reference. The Carll patent discloses a theftalarm system for use with a digital signal PBX telephone system whichincludes a number of electronic tethers connected to individual piecesof protected equipment, each tether including a pair of conductors whichare connected to form a closed current loop via a series resistor andconductive foil adhesively bonded to the equipment. Once assembled, theresulting circuit loop can be used for device removal detection,however, the conductive foil which is bonded to the equipment may becarefully removed without any detection.

The Batolutti patent also referenced above, discloses yet another methodof detection for patch panel connectors themselves. A patch panel onwhich multiple mechanical sensors are mounted, serves to detect thepresence or absence of a patch cord connector in a connector port on thepanel and a computer controller connected to the multiple sensors maythen be used to monitor changes in patch panel connections such as whena connector is removed from a connector port. The detection, however, islimited to the mere absence or presence of a connector.

Providing power to connected devices is yet another consideration duringimprovement development which can often include aspects of devicedetection as described above. Power applications, such as those found inpower over ethernet technologies, allows IP telephones, wireless LANAccess Points and other appliances to receive power while also receivingdata over existing LAN cabling without a need to modify ethernetinfrastructure. Such technologies are described in IEEE802.3af, alsoknown as Power Over Ethernet, which outlines the designs of Ethernetpower-sourcing equipment and powered terminals.

Various methods for providing power to remote devices are also disclosedin U.S. Pat. No. 6,218,930, issued Apr. 17, 2001, to Katzenberg et al.,the subject matter of which is incorporated herein by reference. In oneexample of a power application technology, an initial detection step isused prior to a power application step. Prior to applying external powerto a device, automatic detection of connected equipment is accomplishedby delivering a low level current to the network interface and measuringa voltage drop in the return path. The measurement can have threestates, including no voltage drop, a fixed level voltage drop or avarying level voltage drop. As disclosed in the Katzenberg patent, if novoltage drop is detected, then the remote equipment does not contain aDC resistive termination and this equipment is identified as unable tosupport remote power feed. If a fixed voltage level is detected, theremote equipment contains a DC resistive termination, such as a “bobsmith” termination and this equipment is also identified as being unableto support remote power feed. If a varying voltage level is detected,this detection indicates the presence of a DC-DC switching supply in theremote equipment and this equipment is identified as being able tosupport remote power feed which is then provided.

The attempts to address device movement and detection, as well asattempts to address providing power to connected devices, typically failto consider the communication performance degradation that suchsolutions can create. Where attempts to correct performance degradationhave been made, the solutions have typically been limited to therelocation and manipulation of signal traces. Examples of such solutionsare disclosed in U.S. Pat. No. 5,797,764, issued Aug. 25, 1998, toCoulombe et al., and in U.S. Pat. No. 5,673,009, issued Sep. 30, 1997,to Klas et al., the subject matter of each being incorporated herein byreference. The Coulombe patent discloses a printed circuit boardelectrically coupling a connector block and jack assembly within a patchpanel. Each signal trace on the board is provided a compensation tracealigned either above or below the respective signal trace for anelectromagnetic connection between traces sufficient to reducecrosstalk. Trace manipulation is also disclosed in the Klas patent,which discusses a printed circuit board on which crosstalk is eliminatedthrough the relocation of adjacent traces. Equal and opposite signalsource traces are placed adjacent to one another such that cumulativecrosstalk is eliminated. Unfortunately, trace manipulation is notsufficient in every case to provide category 3, 5, 5e, 6 and/or higherand equivalent performance levels.

Still further examples of such solutions are disclosed in U.S. Pat. No.6,443,777, issued Sep. 3, 2002, to McCurdy et al., and in U.S. Pat. No.6,464,541, issued Oct. 15, 2002, to Hashim et al., the subject matter ofeach being incorporated herein by reference. The McCurdy patentdiscloses an inductive and capacitive crosstalk compensation techniqueincorporated into a communication connector (i.e. modular jack) whichincludes the relocation of contact wires and the addition of a printedwiring board for capacitive coupling. The contact wires are separated bya distance set to obtain an adequate level of inductive compensationcoupling, and a capacitive coupling is provided by one or more printedcircuit boards located in the plug body as the contact wires aredisplaced. The use of such printed wiring boards is also discussed inthe Hashim patent, which also discloses a two stage crosstalkcompensation technique. In a first stage, a printed wiring board isprovided for capacitive coupling as the contact wires are displaced, andin a second stage, a printed wiring board is provided having a number ofinductive loops and carefully positioned comb traces. Although both theMcCurdy and Hashim patents address crosstalk reductions at the connectorposition, each fails to address the performance degradation beyond theconnector, including performance degradation that can be created due toadditional active circuitry elements involved in providing advancedfeatures.

Accordingly, a need exists for an asset aware patch panel that caninclude advanced features for asset management and security, and canalso provide compensation for active electronics used in achieving theseand other advanced features.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a system and method foran asset aware patch panel circuit that can include advanced featurecomponents for use with asset management and security functions,including functions for providing power and detection for remotelyconnected devices.

Another object of the present invention is to provide a system andmethod for an asset aware patch panel circuit that can provide advancedfeature components as either removable modular electronic components oras fixed electronic components located directly on a patch panel printedcircuit board.

Another object of the present invention is to provide a system andmethod for an asset aware patch panel circuit that can providecommunication between an insulation displacement connector (IDC) at aPD/User end and any standard interface type using twisted pair cables,such as an RJ45 connector, at a switch end (i.e. telecommunicationequipment end).

A further object of the present invention is to provide a system andmethod for an asset aware patch panel circuit that can minimize theadverse performance effects on communication created by removablemodular or fixed electronic advanced feature components and provide atleast category 3, 5, 5e, 6 and/or higher (e.g. 6e or 7) and equivalentperformance levels as required.

Yet another object of the present invention is to provide a system andmethod for an asset aware patch panel circuit constructed as a 3U panelwhich includes space for cable management and active circuitry betweentelecommunication circuits arranged above and below the cable managementand active circuitry, including 1 to 120 ports such that density ismaintained.

These and other objects of the present invention are substantiallyachieved by providing an asset aware patch panel circuit that caninclude removable modular or fixed electronic components locateddirectly on a patch panel printed circuit board, which are separately orin combination used in providing advanced features. The advancedfeatures can include detecting the connection presence or absence of aremote device and where applicable, providing a power supply toconnected remote devices including VoIP phones, remote wireless Ethernetdevices and other network devices. The patch panel circuit includes amultilayered patch panel printed circuit board having a plurality oflayers, a communication circuit disposed on a first layer andelectrically coupled between an insulation displacement connector (IDC)at a PD/User end and an RJ45 connector at a switch end, and a removablemodular or fixed electronic component electrically coupled with saidcommunication circuit. The component can include an active circuitdisposed on a second layer for use in providing an advanced feature. Thecircuit further includes compensating circuit elements, which aredisposed directly between signal traces on the first and/or secondlayers, and can also be disposed on a third layer, wherein each elementis provided to establish a compensating capacitance and inductivecoupling with the active circuit to substantially minimize the adverseeffects resulting from the active circuit.

The patch panel circuit and included fixed and/or removable componentscan support devices implementing techniques similar to those ofIEEE802.3af and TIA-568B series, including updates such as TIA568B.1-6.The patch panel circuit and included components are also sufficientlyflexible to provide power to other proprietary device configurations,applications or developing standards that require similar power levels.

The patch panel circuit can also perform data collection functions onvarious system parameters including device connections, locations andpower status conditions at various connection ports. In each case, thepatch panel circuit provides at least category 3, 5, 5e, 6 and/or higher(e.g. 6e or 7) and equivalent performance levels by minimizing theadverse effects of the active fixed and/or removable electronics used inproviding advanced features through the use of inductive, capacitive andreactive circuit elements positioned to compensate for advanced featureelectronics.

Other objects, advantages and salient features of the present inventionwill become apparent from the following detailed description, which,when taken in conjunction with the annexed drawings, discloses apreferred embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring to the drawings which form a part of this disclosure:

FIG. 1 is a block diagram illustrating a data terminal equipment powerinsertion and data collection patch panel circuit in accordance with anembodiment of the present invention;

FIG. 2 is a perspective view from a first angle illustrating a mountingpanel in accordance with an embodiment of the present invention;

FIG. 3 is a perspective view from a second angle illustrating a mountingpanel in accordance with an embodiment of the present invention;

FIG. 4 is a side elevational view illustrating a patch panel assemblyincluding advanced feature electronics in accordance with an embodimentof the present invention;

FIG. 5 is a side elevational view illustrating a patch panel assemblyincluding advanced feature plug-in modules as a parallel mountedfunctionality option board in accordance with an embodiment of thepresent invention;

FIG. 6 is a side elevational view illustrating a patch panel assemblyincluding advanced feature plug-in modules as a perpendicular mountedfunctionality option board in accordance with an embodiment of thepresent invention;

FIG. 7 is a plan view of a layered patch panel printed circuit board inaccordance with an embodiment of the present invention;

FIG. 8 is a schematic illustrating an example of active circuit elementsthat can be disposed on the patch panel printed circuit board for use inproviding detection and power insertion in accordance with an embodimentof the present invention;

FIG. 9 is a trace layout schematic illustrating the circuit of FIG. 8 asdisposed on the patch panel printed circuit board in accordance with anembodiment of the present invention;

FIG. 10 is a trace layout schematic illustrating an effect minimizingcircuit as disposed on the patch panel printed circuit board for usewith the circuit of FIG. 8 in accordance with an embodiment of thepresent invention; and

FIG. 11 is a trace layout schematic illustrating both the effectminimizing circuit of FIG. 10 and the circuit of FIG. 9 in an exampleposition on the patch panel printed circuit board in accordance with anembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention includes an electrical device which functions as apatch panel while providing additional advanced features. Where suchfeatures are provided, the present invention also serves to reduce oreliminate the adverse effects created by the additional featureelectronics through positioning and separation of circuit elements,and/or providing effect minimizing or compensation circuit elements toincrease performance levels.

The present invention can include one or more advanced featurecomponents separately or in combination as either modular plug-in unitsor circuits disposed directly on the patch panel circuit board. Asdescribed in greater detail below, the advanced feature components canbe used to detect devices attached to the patch panel cabling, both forsecurity and to determine the device types with respect to powerrequirements, and further provide DC power to attached devices wherepractical. Power can be provided through techniques similar to thoseoutlined in IEEE802.3af and TIA-568B series, including updates such asTIA568B.1-6 and other developing standards.

The modular feature of the present invention allows such components tobe added and removed in any number of combinations to provide a widerange of desired advanced features to the patch panel, even beyond thoseoutlined above. For example, there are several standards andapplications that need power application other than IEEE802.3af, such asbuilding automation systems, security systems, VoIP and so on, and thereference to IEEE802.3af above is presented as one example of theapplication of the present invention. Also, the modular features of thepresent invention allow for still developing standards, such as thoseassociated with the TIA and IEEE.

The advanced feature components, however, are not restricted to modularunits and can also include fixed circuits or circuit components that aredisposed directly on the patch panel or patch panel printed circuitboard. In each case and specifically in cases where additional featurecircuit components are disposed directly on the patch panel printedcircuit board, the components can create adverse effects which requirecompensation if the patch panel is to achieve desired performancelevels. Such compensation can be provided through techniques such asseparation and selective positioning of advanced feature components andcircuits, and through the addition of active circuit components to thepatch panel printed circuit board.

FIG. 1 is a block diagram 10 illustrating a data terminal equipmentpower insertion and data collection patch panel circuit 12 which caninclude an optional device detection feature 14, a power insertionfeature 16, a port assembly 18 and a data management feature 20 inaccordance with an embodiment of the present invention. An example of aremote device network 22 is also shown, including a communication link24 serving to electrically couple a number of remotely connected devices22(a) through 22(d) with the patch panel circuit 12. As known to thoseskilled in the art, the patch panel circuit typically serves as a linkor connection between such devices and a network file server or switch26.

Each remotely located device 22(a) through 22(d) is connected to thenetwork 26 via the patch panel 12 so as to provide widespread remoteuser access to a network. The remotely located devices 22(a) through22(d) (e.g. personal computers) are shown connected to port assembly 18via a data communication link 24 which includes a plurality of transmitand receive communication lines for communicating information betweeneach of the remotely located devices and a final destination, such asthe network file server 26.

In the embodiment of the present invention shown in FIG. 1, the patchpanel 12 can be used to monitor each remotely located electronic device22(a) through 22(d) using for example, a current loop continuity circuitprovided by the device detection feature 14 as described in greaterdetail below. The device detection feature 14 can be provided as aremovable, modular electronic component, or as a fixed circuit disposeddirectly on a patch panel printed circuit board of the patch panelcircuit 12. In either case, the device detection feature 14 can be usedto monitor the data communication link 24 and detect the presence andremoval of any device from the network 22. The addition of this advancedfeature however, can produce detrimental effects in the communicationperformance of the patch panel circuit 12.

The patch panel circuit 12 can also be used to provide power insertionfor each remotely located electronic device 22(a) through 22(d) usingfor example, the data communication link 24. The communication link 24allows the power insertion feature 16 of the patch panel circuit 12 toprovide equipment power insertion as described in greater detail below.Additional details regarding device detection and power insertion aredisclosed in U.S. Pat. No. 5,406,260 to Cummings et al., referencedabove.

The patch panel circuit 12 of FIG. 1 can further include a datamanagement feature 20 provided to monitor, control and collect data fromthe remote device network 22, device detection feature 14, powerinsertion feature 16 and any additional feature components that may beincluded. The information can be remotely accessed, periodically polledor provided to a network server for system management purposes. As withthe device detection feature 14, the power insertion feature 16 and datamanagement feature 20 can also be provided as removable, modularelectronic components, or fixed circuits disposed directly on a patchpanel printed circuit board and can also produce detrimental effects inthe communication performance of the patch panel circuit 12.

The patch panel circuit 12 of FIG. 1 can be constructed as atelecommunications rack including an adapter panel, a number of patchport assemblies and one or more printed circuit boards. Each patch panelprinted circuit board can be mechanically mounted to an adapter panelthereby providing a platform, or mounting surface for patch panelelectronic components and additional function components.

FIGS. 2 and 3 are perspective views from a first and second angleillustrating a mounting panel in accordance with an embodiment of thepresent invention. FIG. 2 shows a panel 30 front surface having a seriesof cable management mechanisms 34 secured and extending from the panelsurface between a series of port apertures 32. Between the cablemanagement mechanisms and adjacent to each port apertures, a series ofopenings 38 are provided. FIG. 3 shows a panel 30 rear surface having aseries of mounting mechanisms 36 secured and extending from the panelsurface. Each feature of the panel shown in FIGS. 2 and 3 are describedin greater detail below in association with an assembled patch panelprinted circuit board and components.

As noted above, the panel 30 includes a series of cable managementmechanisms, port apertures, openings and mounting mechanisms, upon whicha patch panel printed circuit board and associated components can beassembled and mounted as shown in FIGS. 4, 5 and 6. FIGS. 4, 5 and 6,are side elevational views illustrating an assembled telecommunicationsrack of patch panel circuit 12 in accordance with the present invention.As shown in FIGS. 4 through 6, the front surface of the adapter panel 30includes a series of cable management mechanisms 34 mechanicallyattached adjacent to the series of port apertures 32 and can be used toprovide support, control and protection for various cables associatedwith the patch panel circuit 12. In the example shown, the cablemanagement mechanisms can be constructed as rings having an enclosedcircumference with at least one access opening provided for cableinsertion. The cable management mechanisms of FIGS. 4 through 6 arepresented as one example, and may be constructed in differentarrangements in yet other versions of the present invention as requiredby the application. The adapter panel 30 also includes a series ofopenings 38 between the front and rear surface of the adapter panel 30,allowing access between surfaces for use in cable routing and modularplug installations as described in greater detail below.

The rear surface of the adapter panel 30 can include one or more printedcircuit boards 40 mechanically mounted via a series of mounting posts 36extending from the rear surface of the adapter panel. The mounting postscan be constructed having a threaded inside diameter to receive athreaded connector via one or more mounting holes located on the printedcircuit boards or circuit modules. One or more mounting posts 36 canalso be used as an electrical ground connection between a ground planeof an attached printed circuit board and the adapter panel. In yetanother version of the present invention, the mounting posts 36 can bereplaced by one or more plastic support members having a snap fit orsimilar mechanism at each end as known to those skilled in the art.

Each mounting mechanism described above can be used to secure one ormore printed circuit boards to the rear surface of the adapter panel 30upon which both signal routing and advanced feature components can bepositioned as shown in FIGS. 4 through 6. In FIG. 4, a patch panelprinted circuit board 40 is shown mounted parallel to the rear surfaceof the adapter panel 30, thereby providing an exposed and accessiblemounting surface for additional feature components and/or modules, suchas the device detection feature 14, power insertion feature 16 and datamanagement feature 20. The additional feature components and/or modulescan be disposed directly upon the printed circuit board 40, orelectrically coupled as modules, including parallel modular printedcircuit boards as shown in FIG. 5, or perpendicular modular printedcircuit boards as in FIG. 6. In FIG. 5, an additional feature, oradditional functionality option board 48 is shown mounted parallel tothe surface of the patch panel printed circuit board 40, and in FIG. 6,an additional feature printed circuit board 50 is shown mountedperpendicular to the patch panel printed circuit board 40, each usingdirect modular or flexible connections 45 to electrically couple eachprinted circuit board 40, 48 and 50.

A number of coupling devices, such as patch port assemblies 44, can alsobe positioned on the surface of the printed circuit board 40 tointerface with various cabling routed along the front surface of theadapter panel. The coupling devices, shown extending between the surfaceof the printed circuit board 40 and the front surface of the adapterpanel 30 via port apertures 32, can be used to terminate cabling routedthrough the cable management mechanisms 34 without requiring directaccess to the printed circuit boards 40, 48 or 50, and provide theelectrical circuit between an insulation displacement connector (IDC)and a modular RJ45 connector as described in greater detail below.

Returning to FIG. 4, the printed circuit board 40 can accommodate therequired electronic circuitry 46 for the advanced feature circuitsdirectly on the surface area of the patch panel printed circuit board40, or as shown in FIGS. 5 and 6, the advanced feature components can bemodular and coupled with the printed circuit board 40 in any number ofcombinations. These advanced feature circuits of FIGS. 4 through 6,components 46, 48, and 50 respectively, can include the devicedetection, power insertion, and management features of FIG. 1, inaddition to any number of additional advanced features available. Eachadvanced feature circuit can be added, upgraded, removed, or replacedaccording to the desired level of functionality desired withoutreplacing the entire patch panel 12 or patch panel printed circuit board40 and incurring additional rewiring costs.

Once assembled, the patch panel printed circuit board 40 can be used toprovide a communication circuit between, for example, an insulationdisplacement connector at a PD/User end, and any standard interface typeusing unshielded twisted pair cables, such as an RJ45 connector at aswitch end. As constructed, the present invention can include a 3U panelwhich has space for cable management and active circuitry betweentelecommunication circuits that are arranged above and below the cablemanagement and active circuitry, and including 1 to 120 ports per unitsuch that density is maintained.

As known to those skilled in the art, the required electronic circuitryfor the advanced feature circuits 46, 48 and 50, typically includes acertain amount of active circuitry. Where these circuits are provided asplug-in modules or positioned on the printed circuit board 40, a degreeof patch panel performance degradation can be created due to the activecircuitry elements involved. The printed circuit board 40 of the presentinvention however, is configured to compensate for this degradation andprovide category 3, 5, 5e, 6 and/or higher (e.g. 6e or 7) and equivalentperformance levels as required. Specifically, the present inventionincludes a patch panel circuit having a number of techniques tosignificantly minimize the impact of such performance degradation.

A first compensation technique used in accordance with the presentinvention is achieved through patch panel printed circuit board designand layer separation. As shown in FIG. 7, the present inventionconstructs the printed circuit board 40 as an ordered multi-layeredpanel to separate the signal layers, such as the traditionaltelecommunication signals and the like (e.g., Ethernet signals), fromthe active circuits. FIG. 7 is a plan view of a layered patch panelprinted circuit board assembly illustrating individual layer views ofthe patch panel printed circuit board 40 in accordance with the presentinvention.

The active circuitry of the patch panel circuit 12 typically includesany detection circuitry, operational amplifiers and other componentsnecessary for logical operations and power insertion in the patch panelnetwork. Additional details regarding such circuitry are disclosed inU.S. Pat. No. 5,406,260 to Cummings et al., referenced above. In thepresent invention, this active circuitry is positioned on one or morelayers of the printed circuit board 40, which are then separated fromremaining layers as described below.

In the example shown in FIG. 7, the printed circuit board panel 40 ofpatch panel 12 is constructed of at least 8 layers, and includes layers52 through 66 upon which components, features and signal traces can beseparated yet still provide an electrical circuit between an IDC and anRJ45 connector in accordance with an embodiment of the presentinvention. In the multi-layer patch panel of FIG. 7, the signal layersoccupy the first two or more layers, beneath which are ground and powerlayers that provide isolation. The remaining one or more layers containthe components and routing for the active circuits which are separatedfrom the signal, or telecommunication circuitry by placement in layersthat are isolated by the ground and/or power planes. One example of thelayers of the printed circuit board 40 are defined below in Table 1.

TABLE 1 Layer Function 52 Telecommunication circuit with signal carryingtraces and a limited number of compensation circuitry. This layer alsocan include components which need to be part of, or in close proximityto the signal traces. 54 Telecommunication circuit with compensationcircuitry and a limited number of signal carrying traces. 56 Groundplane. 58 Ground plane. 60 Power plane (e.g. +8 to +15 V). 62 Powerplane (e.g. +5 V). 64 Active circuit secondary routing layer. 66 Activecomponents, IDC components, plug-in module connectors and primaryrouting for active circuitry.

When combined, the layers of the printed circuit board 40 provide anelectric circuit for interfacing the field wiring with the system wiringand advanced features. In doing so, the circuit participation of eachlayer of printed circuit board 40 can be described as follows.

On layer 52, telecommunication circuits 53, each with signal carryingtraces and compensation circuits are used to provide communicationsbetween a user end and switch end. Also, as discussed in greater detailbelow in regards to a second compensation technique, a series ofcompensating circuit elements 68 are positioned in the span of thesignal layer. Between layers 52 and 54, is a first of several prepreglayers.

Below the first prepreg layer, a routing layer 54 is included (e.g., anEthernet signal trace layer), followed by a first of several core layersor conventional insulator sheets, and provides a telecommunicationcircuit with a limited number of signal carrying traces. Below the firstcore layer are layers 56 and 58, which are electrical ground planesseparated by a second prepreg layer and followed by a second core layer.Below the second core layer is a voltage plane layer 60 and 62, whichare separated by a third prepreg layer and followed by a third corelayer. Below the third core layer is layer 64, including the activecircuit secondary routing 65, which is followed by a fourth prepreglayer. Below the fourth prepreg layer is layer 66, including the activecomponents 67, primary routing for active circuitry, and IDCconnections.

The active circuitry of the advanced features located on, or coupledwith layers 64 and 66 can result in patch panel performance degradationat the communication layer which should be corrected to provide desiredperformance levels. As noted, this active circuitry 65 and 67 typicallyincludes the detection circuitry, operational amplifiers and othercomponents necessary for the logical operations, and additional featuressuch as visual connection indicating lights and power insertioncircuitry as disclosed in U.S. Pat. No. 5,406,260 to Cummings et al.referenced above. The separation of layers as shown in FIG. 7 providesfor performance improvements in both the communication circuits oflayers 52 and 54, and in the active circuit layers 64 and 66 byeliminating the noise interaction and shielding the communication layersfrom the circuit elements operating on the active circuit layers.

In the present invention, the active circuit layers are separated fromthe communication circuit layers by multiple electrical ground layers,core layers and prepreg layers. The voltage planes, layers 60 and 62,are placed adjacent to the active circuit layers whereas electricalground planes 56 and 58, are placed adjacent to the communicationcircuit layers, as typically less noise results from such ground planes.The combined layers 56, 58, 60 and 62 still further contribute toperformance improvements by providing a greater separation distancebetween communication and active circuit layers than typically found.Additionally, as described in greater detail below in association withthe second compensation technique, a number of compensating circuitelements 68 can be positioned on layers 52 and 54 to further increasethe performance level of the patch panel circuit board 40 when advancedfeature electronics are added or removed.

A second compensation technique used in accordance with the presentinvention is achieved by providing compensating circuit elements on thepatch panel printed circuit board. The compensating circuit elements ofthe printed circuit board 40 of the present invention are more clearlyshown in FIGS. 10 and 11, and function in relation to the additionalcircuit elements as shown in FIGS. 8, 9 and 11. FIG. 8 is a schematic 80illustrating an example of additional feature components such as thoseprovided to divide the communication circuit into separate input andoutput circuits on the signal layer for insertion of device detectionand power features. FIG. 9 is a layout schematic illustrating thecircuit of FIG. 8 on the patch panel printed circuit board, and FIG. 10is a layout schematic illustrating the compensating circuit elements foruse with the circuit of FIG. 8 in accordance with an embodiment of thepresent invention. FIG. 11 is a layout schematic illustrating both thecompensating circuit elements of FIG. 10 and the circuit of FIG. 9 in anexample position on the patch panel printed circuit board 40 inaccordance with the second compensation technique.

In FIG. 8, a schematic 80 is shown illustrating a partial electricalschematic of the patch panel printed circuit board 40 including severalcomponents for use with providing additional features. In addition,coupling points to advanced feature electronics are also shown. As shownin FIG. 8, schematic 80 of the patch panel printed circuit board 40includes a number of fixed active components, signal routes, andbridging circuits 72 which can be used for signal routing and couplingpoints for any number of advanced feature components which providedevice detection and power insertion at the patch panel via themulti-conductor link between devices and the network system. An exampleof one multi-conductor link between devices and the network systemprovided by the patch panel circuit board 40 includes a plurality oftransmit and receive communication lines or signal traces, such as lines82-1 through 82-8, for communicating information between devices, suchas the devices 22(a) through 22(d) of FIG. 1 and a server or switch viathe patch panel printed circuit board 40.

In the example shown in FIG. 8, the communication lines 82-1 through82-2 can be routed through the patch panel along the first and secondlayers 52 and 54 of the patch panel printed circuit board 40 andterminate at an IDC at a PD/User end 84, and any standard interface typeusing twisted pair cables, such as an RJ45 connector at a switch end 86.The twisted pair cables commonly consist of unshielded twisted pair(UTP), shielded (STP), and variations of STP known as screened twistedpair (ScTP) and foil twisted pair (FTP). The RJ45 connector becomesindependent from the IDC contacts due to a series of DC blockingcapacitors described in greater detail below. The RJ45 dc looprepresents a switch/server/active network equipment side, while the IDCdc loop represents the terminal equipment/power device side.

Where components providing advanced features are located on the printedcircuit board 40, the components would comprise part of the activecircuitry located on layers 64 and 66 of the multilayer printed circuitboard 40. As shown in FIG. 8, the advanced feature components can becoupled with the signal traces, therefore several circuit componentsbridge the communication and active circuitry layers.

In FIG. 8, a power insertion module or electronics (not shown) can becoupled with leads 87 of schematic 80 and in doing so, power can beinserted onto the differential transmission link pairs 82-4 and 82-5,and pairs 82-7 and 82-8. The remote power can be inserted usingcenter-tapped transformers 91 and 92 respectively, connected between twopins of each conductor pair and provide DC power to the remote devicescoupled to the transmission link. The signal flow in each pair however,is not interrupted by such power insertion which allows the operation ofapplications that require all four conductor pairs, such as gigabitEthernet.

A detection module or electronics (not shown) can also be coupled withleads 88 of the circuit and the multi-conductor link. Both the detectionperformed on conductor pairs and power insertion are implemented throughtechniques such as those defined in IEEE802.3af and TIA-568B, includingupdates, such as TIA-568B.1-6. In this manner, detection can be achievedby the detection module or electronics, such as when detecting thepresence and removal of any device from the network via a current loopcontinuity circuit through conductor pairs. Using conductors 82-1, 82-2,82-3 and 82-4, the detection module can establish the existence of adevice at the end of the cabling plant and the use of these conductorpairs allows the detection of devices that utilize only these pairs,which are typically referred to as the “signal pairs” in 10 Base-T and100 Base-T applications.

As shown in FIG. 8, a number of fixed active components, signal routes,and bridging circuits 72 are used for routing and coupling points forthe advanced feature components described above. Where such advancedfeature modules or electronics are coupled with circuit, the electricalcharacteristics and performance of the communication circuitry willtypically be reduced. The performance degradation can be minimizedthrough design and layering using the first compensation techniquedescribed above, however, the performance degradation can also beminimized through compensating circuit elements using the secondcompensation technique described in greater detail below.

Therefore, the second compensation technique used in accordance with anembodiment of the present invention includes providing a series ofcompensating circuit elements, and positioning each on the printedcircuit board 40 relative to the advanced feature active circuitelectronics described above. As shown in FIG. 8, the active circuit 72includes center-tapped transformers 91 and 92, and a series of DCblocking capacitors 101 through 108 placed on the patch panel printedcircuit board in the span of the signal layer to divide the circuit intoseparate input and output segments. The blocking capacitors are used toblock the DC signal and separate the terminal, or device side from theserver side. The use of the blocking capacitors allows the delivery ofDC power to only the terminal side without delivering power to theserver side. In doing so, the circuit provides separate DC-loops for thecable termination section of the panel and the modular plug connections.As a result, no DC continuity can be obtained between the IDC and RJ45terminations, however, AC and RF continuity is still maintained.

The selection of the proper blocking capacitor size is important toensure a minimal impact on the performance of the communicationcircuitry. An example of capacitor values found in circuit are definedin Table 2.

TABLE 2 Pin Capacitor Value Minimum Value Maximum Value 82-1 0.1 μF 0.020.5 82-2 0.1 μF 0.02 0.5 82-3 0.027 μF 0.01 0.1 82-4 0.1 μF 0.02 0.582-5 0.1 μF 0.02 0.5 82-6 0.027 μF 0.01 0.1 82-7 0.1 μF 0.02 0.5 82-80.1 μF 0.02 0.5

The active circuit elements 72 of the printed circuit board 40 alsoincludes center-tapped transformers 91 and 92 which form a DC insertionpath into the communication circuitry. These transformers bridge theactive and communication circuits and allow DC current to pass, but donot affect the higher frequency performance of the differential signalsthat are typically operating over the same conductor pairs. As withcapacitors 101 through 108, transformers 91 and 92 are also selected andplaced on the patch panel printed circuit board to ensure a minimalimpact on the performance level of the patch panel circuit board 40.

However, regardless of selection, the active circuitry 72 of theadvanced features located on layers 64 and 66 can still result in patchpanel performance degradation at the communication layer. To minimizethese effects, a series of compensating circuit elements are positionedin the span of the signal layer and a degree of inductive coupling isalso provided on the signal layer. As more clearly shown in FIGS. 8 and9, the active circuitry 72 is disposed on layers 64 and 66 of the patchpanel printed circuit board 40 and is comprised in part of capacitors101 through 108 positioned at points labeled 74. FIG. 9 illustrates atleast one layer of a portion of a patch panel printed circuit boardlayer surface, upon which the capacitors 101 through 108 are provided inseries with the circuit traces extending on layers 64 and 66 and shownlabeled 76. The placements shown in FIG. 9 are presented as one example.

In FIG. 10, a series of compensating circuit elements are shownpositioned in the span of the signal layers 52 and 54 of the patch panelprinted circuit board 40. FIG. 10 illustrates at least another layer ofa portion of a patch panel printed circuit board layer surface, uponwhich the compensating circuit elements are provided, shown at pointslabeled 78. These compensating circuit elements include inductive,capacitive and reactive elements which serve to compensate for theadverse effects of the active circuit elements disposed on layers 64 and66. As known to those skilled in the art, printed circuit board tracesare typically constructed of foil or copper-clad foil materials andestablish capacitance and inductive coupling with adjacent traces on thesame or different layers. Typically, such traces are provided with gapsof approximately three times the trace width to minimize thiscapacitance and inductive coupling, however the beneficial use of suchparasitic effects can be achieved through alternate placements. In theexample shown in FIG. 10, the compensating circuit elements areconstructed as interdigital comb traces on at least one layer of theprinted circuit board 40, however, each (i.e., inductive, capacitive andreactive elements) can be provided on any layer as required. Forexample, inductive coupling is provided on layers including signaltraces.

As shown in FIG. 10, a series of such traces are provided in thecompensating circuit elements shown at points labeled 78. In the exampleshown in FIG. 10, the series of traces are provided on the signal layers52 and 54 and are positioned relative to the capacitors and capacitortraces shown at points labeled 74 and 76 on layers 64 and 66 of thepatch panel printed circuit board. In the examples shown in FIG. 10, thepositioning of the elements 68 is provided as only one example, and canbe reconfigured as required given different capacitor positioning at theactive circuit layer.

In FIG. 11, an example of a completed assembly in accordance with anembodiment of the present invention is shown, wherein the positioningbetween the capacitors and capacitor traces on layers 64 and 66 of FIG.9, and the compensating circuit elements on the signal layers 52 and 54of FIG. 10 is illustrated. Specifically, the compensating circuitelements on the signal layers (i.e. capacitors, or any inductivecoupling or other compensation method), are positioned to couple, orcompensate, between the traces of the communication circuit. Thiscoupling/compensation restores balance (i.e. return loss and impedance),to the circuit and reduces or cancels any noise that results from theunbalance, including near end crosstalk (NEXT), far end crosstalk(FEXT), and the like. In such a configuration, the beneficial parasiticeffects of the compensating circuit elements can be used to increase theperformance level of the patch panel circuit board 40 when advancedfeature electronics are added.

Therefore, in addition to the printed circuit board layer separationdescribed above, the present invention can further include theinductive, capacitive and reactive elements of the compensating circuits68 on the patch panel printed circuit board 40 to compensate for theeffect of the added advanced feature electronics 72 placed on the board40 and minimize effects thereof on signal paths. Remaining effects areminimized through the use of high impedance connection and blockingtechniques. Specifically, the advanced feature active circuitry coupledwith the present invention interfaces with the cabling which connectsthe hardware signal patch in two methods. First, through high impedanceconnections that “tap” the communication circuitry, or through“blocking”, or series devices that are located within the span of thenetwork. The high impedance connections also minimize the effect of theadvanced feature electronics on the performance of the signal path.Additionally, the selection of blocking capacitor values as shown inTable 2 minimizes the effect on return loss and attenuation that thecomponents may create.

The present invention can be configured as a single unit with all orpartial functionality, or a multiple unit including additionalfunctionality option boards and connectors as shown in FIGS. 4 through6. The present invention can be a single or multi-port device, includingfrom 1 to 120 ports per unit, exceeding currently available levels of 24to 48 ports per unit, and providing a connecting point for modularconnectors. The patch panel printed circuit board is sized to occupyapproximately three rack units (3U, or approx. 3×1.75″) and maintain thedensity of the ports in the final panel as cable management can now bepart of the same patch panel. As constructed, the present invention caninclude a 3U panel which has space for cable management and activecircuitry between telecommunication circuits that are arranged above andbelow the cable management and active circuitry, including 1 to 120ports per unit such that density is maintained. The present inventionalso provides at least one modular connector as an output, typically anRJ45 connector, which interfaces with a modular plug. The abovecombinations allows the construction of a patch panel including cablemanagement, active circuitry within a 3U panel size, and specifically,the ability to obtain at least 48 ports and associated cable managementin a 3U panel size.

The present invention described above provides communication hardwarethat is capable of at least category 3, 5, 5e, 6 and/or higher (e.g. 6eor 7) and equivalent performance levels as required, and also maintainscategory transmission performance as defined in IEEE802.3 and TIA-568Btransmission requirements. The present invention can be hardwired to thecabling plant and thus, can also be used to collect and provideinformation about the location of attached devices via a data managementfeature. This can be particularly important for services such asemergency 911 applications where the location of the calling party iscritical to determine, especially when on a VoIP network.

While one embodiment has been chosen to illustrate the invention, itwill be understood by those skilled in the art that various changes andmodifications can be made therein without departing from the scope ofthe invention as defined in the appended claims.

1. A compensating advanced feature patch panel that can include removable modular or fixed electronic components, wherein the patch panel provides improved performance levels, said patch panel comprising: a multilayered patch panel printed circuit board comprising a plurality of layers; a communication circuit disposed on at least a first layer of said plurality and electrically coupled between an insulation displacement connector (IDC) at a PD/User end and an RJ45 connector at a telecommunication equipment end; at least one of a removable modular or fixed electronic component electrically coupled with said communication circuit, said component comprised of at least one active circuit disposed on at least a second layer of said plurality to provide an advanced feature; and a plurality of compensating circuit elements disposed upon at least one layer of said plurality to establish a compensating capacitance and inductive coupling with said active circuit to substantially minimize at least one adverse effect resulting from said active circuit and thereby providing improved performance levels.
 2. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said communication circuit includes at least one of a signal carrying trace or a telecommunication routing circuit.
 3. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said advanced feature includes at least one of a device detection feature, logical operation feature and power insertion feature.
 4. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said active circuit includes at least one of an active circuit secondary routing layer, active circuit component, IDC component, plug-in module connector and primary routing for active circuitry.
 5. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 4, wherein said active circuit component includes at least one DC blocking capacitor.
 6. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 4, wherein said active circuit component includes at least one center-tapped transformer.
 7. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 4, wherein said active circuit component includes at least one operational amplifier.
 8. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said plurality of compensating circuit elements disposed upon said at least one layer includes at least one of an inductive, capacitive and reactive element to establish said compensating coupling with said active circuit.
 9. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 8, wherein said inductive, capacitive and reactive element is comprised of a signal carrying trace.
 10. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 8, wherein said inductive, capacitive and reactive element is comprised of a conductive foil capacitor circuit.
 11. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said adverse effect includes at least one of an increased noise level, reflection, adverse inductive coupling and adverse capacitive coupling.
 12. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said improved performance levels include at least one of a category 3, 5, 5e, 6, 6e and 7 performance levels and higher.
 13. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said multilayered patch panel printed circuit board further comprises a 3U panel size having at least 48 ports.
 14. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said multilayered patch panel printed circuit board further consists of a panel having at least 48 ports and at least one of a height dimension of 1U, 2U and 3U.
 15. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said multilayered patch panel printed circuit board further comprises a cable management mechanism.
 16. A compensating advanced feature patch panel that can include removable modular or fixed electronic components as claimed in claim 1, wherein said multilayered patch panel printed circuit board further comprises said active circuit and cable management mechanism arranged adjacent to and between said communication circuit upon a surface of said patch panel printed circuit board.
 17. A method of making an advanced feature patch panel that can include removable modular or fixed electronic components which are separately or in combination capable of providing advanced features such as device detection and power insertion, wherein the patch panel provides improved performance levels, said method comprising the steps of: assembling a multilayered patch panel printed circuit board having a plurality of layers; disposing upon at least a first layer of said plurality a communication circuit, said communication circuit electrically coupled between an insulation displacement connector (IDC) at a PD/User end and an RJ45 connector at a telecommunication equipment end; disposing upon at least a second layer of said plurality at least one of a removable modular and fixed electronic component electrically coupled with said communication circuit, said component comprised of at least one active circuit for use in providing an advanced feature; and disposing upon at least one layer of said plurality a compensating circuit element to establish a compensating capacitance and inductive coupling with said active circuit to substantially minimize at least one adverse effect resulting from said active circuit and thereby providing improved performance levels.
 18. A method of making an advanced feature patch panel as claimed in claim 17, further comprising the step of disposing upon said first layer of said plurality a communication circuit including at least one of a signal carrying trace or a telecommunication routing circuit.
 19. A method of making an advanced feature patch panel as claimed in claim 17, further comprising the step of disposing upon said second layer of said plurality at least one of a removable modular or fixed electronic component including at least one of an active circuit secondary routing layer, active circuit component, IDC component, plug-in module connector and primary routing for active circuitry.
 20. A method of making an advanced feature patch panel as claimed in claim 19, wherein said active circuit component includes at least one DC blocking capacitor.
 21. A method of making an advanced feature patch panel as claimed in claim 19, wherein said active circuit component includes at least one center-tapped transformer.
 22. A method of making an advanced feature patch panel as claimed in claim 19, wherein said active circuit component includes at least one operational amplifier.
 23. A method of making an advanced feature patch panel as claimed in claim 17, wherein said compensating circuit element disposed upon said at least one layer includes at least one of an inductive, capacitive and reactive element to establish said compensating coupling with said active circuit.
 24. A method of making an advanced feature patch panel as claimed in claim 17, wherein said adverse effect includes at least one of an increased noise level, reflection, adverse inductive coupling and adverse capacitive coupling.
 25. A method of making an advanced feature patch panel as claimed in claim 17, wherein said improved performance levels include at least one of a category 3, 5, 5e, 6, 6e and 7 performance level and higher. 